Sums of Binomial Determinants, Non-intersecting Lattice Paths and Positivity of Chern-schwartz-macpherson Classes

نویسنده

  • LEONARDO CONSTANTIN MIHALCEA
چکیده

We give a combinatorial interpretation of a certain positivity conjecture of Chern-SchwartzMacPherson classes, as stated by P. Aluffi and the author in a previous paper. It translates into a positivity property for a sum of p × p determinants consisting of binomial coefficients, generalizing the classical Theorem of Lindström-Gessel-Viennot et al. which computes these determinants in terms of non-intersecting lattice paths. We prove this conjecture for p = 2, 3.

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تاریخ انتشار 2008